Fucoidan isolated from the popular edible brown seaweed Sargassum fusiforme suppresses lipopolysaccharide-induced inflammation by blocking NF-κB signal pathway

Abstract

The anti-inflammatory effect of a fucoidan with a molecular weight of 102.67 kDa isolated from an enzymatic digest of Sargassum fusiforme was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that the fucoidan significantly and dose-dependently inhibited the production of inflammatory molecules, including tumor necrosis factor-alpha (TNF-α), nitric oxide (NO), prostaglandin E2 (PGE2), interleukin-1 beta (IL-1β), and interleukin-6 (IL-6), as well as improved the viability of LPS-stimulated RAW 264.7 cells. Moreover, the fucoidan suppressed the expression of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) by regulating the nuclear factor kappa B (NF-κB) pathway in LPS-stimulated RAW 264.7 cells. Furthermore, in vivo test results suggested that the fucoidan remarkably reduced reactive oxygen species (ROS), cell death, and NO levels in LPS-stimulated zebrafish in a dose-dependent manner. Taken together, these results demonstrated that the fucoidan isolated from S. fusiforme possesses strong anti-inflammatory activities in vitro and in vivo, and could prove as an important candidate to be used to develop anti-inflammatory agents in pharmaceutical and cosmeceutical industries.